Water Management Protects Our Environment
Effective management of agricultural irrigation runoff and stormwater discharge is essential to protect local water quality and meet regulatory requirements.

About the Water Quality Management Plan (WQMP)
The Water Quality Management Plan (WQMP) is VCAILG’s roadmap for helping growers comply with the Agricultural Order (Ag Order) requirements of the Los Angeles Regional Water Quality Control Board. Updated every few years, the WQMP outlines the strategies, timelines, and management practices that landowners and growers need to follow to protect water quality and meet regulatory requirements.
The WQMP is organized around Responsibility Areas (RAs), which divide Ventura County into distinct regions based on Total Maximum Daily Load (TMDL) boundaries, subwatershed, and crop types. Each RA has an assigned monitoring site that represents water quality conditions across the area.
Latest WQMP Update
- New RA boundaries: In April 2025, the Los Angeles Regional Water Quality Control Board approved updated Responsibility Area boundaries through VCAILG’s Monitoring and Reporting Plan (MRP). These boundaries were required to address new TMDL compliance obligations.
- 2025 WQMP submission: VCAILG submitted an updated WQMP in May 2025 reflecting the new RA boundaries. This plan is pending approval by the Regional Board. Access a copy here:
2025 Water Quality Management Plan (PDF)
How the WQMP Works
Responsibility Areas: Ventura County is divided into 31 Responsibility Areas based primarily on Total Maximum Daily Load (TMDL) requirements, while also accounting for subwatersheds, drainage patterns, and crop similarities.
Representative Monitoring Sites: Each Responsibility Area has one assigned water quality monitoring site that is considered representative of the larger RA. Water quality results from these sites are used to assess compliance with Ag Order benchmarks and TMDL load allocations.
Enrollee Accountability: If monitoring shows water quality issues, landowner and grower enrollees in that Responsibility Area must implement targeted Management Practices (MPs).

Responsibility Area Complinace Summaries
To make the WQMP more practical for growers, VCAILG provides Responsibility Area (RA) Compliance Summary Handouts. Each handout condenses the WQMP into an easy-to-use reference with:
- Summary of compliance obligations under the Ag Order
- Overview of water quality conditions in the RA
- Required and recommended management practices to implement on the farm
Download your RA Compliance Summary Handout from the links below. To locate the RA assignment of your parcel(s), review the VCAILG Membership and RA Assignments list and search by APN. For further assistance about RA assignment, contact VCAILG at [email protected].
Calleguas and Malibu Creek Watershed Responsibility Area Compliance Summaries

RA 1 – Arroyo Simi
RA 2 – Upper Conejo
RA 3 – Lower Conejo
RA 4 – Calleguas-Howard
RA 5 – Lower Las Posas
RA 6 – Calleguas-CSUCI
RA 7 – Upper Las Posas
RA 8 – East Camarillo Hills
RA 9 – Lower Revolon
RA 10 – Beardsley Wash
RA 11 – Lower Calleguas Creek
RA 12 – Mugu Lagoon
RA 13 – Oxnard Drain #3
RA 15 – Malibu
RA 16 – Malibu – Las Virgenes
Oxnard Coastal Watershed Responsibility Area Compliance Summaries

Santa Clara River Watersheds Responsibility Area Compliance Summaries

Ventura River and Ventura Coastal Watershed Responsibility Area Compliance Summaries
